Zinc/manganese dioxide (Zn/MnO2) power cells are widely used in the primary (disposable) battery market. Such power cells include alkaline, LeClanche, and zinc chloride power cells. The positive electrode of zinc/manganese dioxide batteries generally comprises a manganese dioxide (MnO2) component, graphite, and other additives, such as polymer binders. A specific form of manganese dioxide that is prepared from the electrolysis of hot MnSO4 at a graphite, titanium, or lead alloy anode is electrolytic manganese dioxide (EMD).
The cell capacity directly relates to the lifetime of the cell or the time until a secondary (rechargeable) cell needs recharging. To be commercially viable, a secondary cell should cycle a reasonable number of times before the capacity of the cell drops below acceptable values. To meet ever increasing demands on portable power cells, there is market pressure to increase the volume capacity of portable power cells.